Method of controlling the steam in treatment chambers for textile materials



Sept. 26, 1967 G. SCHIFFER 3,343,187

METHOD OF CONTROLLING THE STEAM IN TREATMENT CHAMBERS FOR TEXTILE MATERIALS Filed March 1, 1965 FB/ W United States Patent 2 Claims. 01. s-149.3

The present invention relates to a method of steamtreating textile materials in form of strands or webs in chambers, steaming apparatuses, bleaching J-boxes or the like, which are not pressure-tight.

In connection with such steam treatment, it is known to heat the goods to be treated by blowing steam, preferably saturated steam, into the treatment chamber and to maintain such steam therein in such quantity that all air will be displaced from the treatment chamber while air is prevented from entering thereinto in order to prevent harmful reactions of air with chemicals with which the goods to be steamed have previously been treated. For economic reasons, it is, on the other hand, important to avoid any material excess of steam to be blown into the treatment chamber inasmuch as such excess would represent a heat loss and in addition thereto would cause excessive steam to enter the work rooms which would then have to be freed from interfering vapors.

The steam consumption depends on the quantity of the goods to be heated and the humidity contents thereof. When a change is effected in the quantity of the goods being passed through the treatment chamber per time unit, or when the loading of the goods into the treatment chamber is being interrupted, it is necessary to change the quantity of steam being blown into the treatment chamber per time unit in conformity with the changed conditions just outlined.

-In an effort to avoid faulty operation and to save personnel, it has been customary in recent times to control the steam supply automatically, and, more specifically, in conformity with the temperature in the treatment chamber. Such a control, Which is temperature dependent, has, however, proved faulty inasmuch as it cannot take into consideration many conditions with regard to temporary steam quality. Depending on the cross section and the length of the steam distributing conduit system and the respective quantity of steam being withdrawn at the stations of consumption, not only the temperature but also the degree of saturation of the steam varies and frequently it occurs that the steam is overheated. If, for instance, the controlling device is set for a rated temperature of 98 C., the steam supply governed thereby corresponds to those values for temperature, pressure and saturation which were measured or ascertained at the very instant at which the controlling device was set. If, however, the steam is slightly overheated, it is possible to reach the temperature of 98 C. with a reduced quantity of steam so that, a result thereof, air is drawn into the treatment chamber through the inlet opening for the goods. Inversely, when the steam in the treatment chamber is somewhat under-cooled, the controlling device will cause an undue large quantity of steam being blown into the treatment chamber in order to be able to reach the 3,343,187 Patented Sept. 26, 1967 rated value. This in turn will cause a considerable quantity of steam to be blown into the work rooms.

It is, therefore, an object of the present invention to provide a method of controlling the steam in a steam treatment chamber, which will overcome the above mentioned drawbacks.

It is another object of this invention to provide a method of automaticaly controllingthe steam in a treatment chamber in such a way that air will be prevented from entering the treatment chamber While, on the other hand, it will be avoided that any material quantity of steam be blown into the work rooms.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawing diagrammatically illustrating partly in view and partly in section an arrangement according to the present invention in connection with a .I-box of a bleaching range.

More specifically, the J-box 1 illustrated in the drawing is of a customary construction and is provided with a discharge elbow 2 forming the lower portion of the l box. The upper portion of the J-box and, more specifically, its inlet for the goods, is closed by a steaming dome 3 which houses a folding device 4. The goods 5 introduced into the steaming dome 3 through a narrow feeding conduit 6 pass over a roller 7 into the J-box and are folded in a zig-zag manner by means of said folding device 4 which may be of any standard design well-known in the art. The steam required for heating up the goods is supplied into the steam dome 3 from a source of steam (not shown) through a conduit 8 and a nozzle chamber 9.

The steam supply is controlled by a pressure gauge 10, for instance a fine pressure gauge having a measuring range of only from zero to 300 millimeters water column, inasmuch as the pressure in steam dome 3 only slightly exceeds the atmospheric pressure. Gauge 10 communicates through a pipe line 11 with the interior of J-box 1. The point of connection of pipe line 11 with J-box 1 is expediently located as far as possible away from the steam inlet but has to be located so that it cannot be clogged up or closed by the folded goods. Gauge 10 is coupled to an impulse emitter 12, for instance with an electric resistance impulse emitter, which through an electric conductor 13 is adapted to act upon a controlling device 14 for controlling a control valve 15 in steam supply line 8. Advantageously, a pneumatic control device 14 is employed which operates in a very sensitive manner. Such a control device, which is well-known in the art, receives the working air from a source of compressed air through a conduit 16 and through a conduit 17 acts upon the diaphragm of a steam control valve 15 in steam supply line 8.

Advantageously, gauge 10 is arranged outside/the influence of heat and humidity in the neighborhood of control device 14 and control valve 15 while communicating with the measuring station through a pipe line of sufficient cross section.

It is, of course, to be understood that the present invention is, by no means, limited to the particular method and arrangement described above but also comprises any modifications within the scope of the appended claims.

What I claim is:

1. A method of controlling the steam in a closed treatment chamber for textile materials which is exposed to 3 3 external atmospheric pressure, in which said materials pass into and out of said chamber through inlet and outlet openings exposed to said atmospheric pressure, said openings allowing gases to pass into and out of said chamber under sufiicient differential pressures, said method comprising admitting steam under pressure into said chamber, sensing the pressure of said steam in said chamber, and controlling the admission of said steam to maintain said steam in said chamber at a constant pressure which is above atmospheric pressure to provide treatment of said materials, but belowthe pressure which would allow the escape of a substantial amount of steam through said inlet and outlet openings.

2. A method as claimed in claim 1, in which the pressure of said steam in said chamber does not exceed 300 millimeters water column.

References Cited UNITED STATES PATENTS 473,398 4/1892 Kirk et al. 687 1,266,265 4/1918 Hoffman 686 2,029,985 2/ 1936 Clark et al.

2,664,010 12/1953 Emerson 685 2,767,568 10/1956 Pope 685 3,067,602 12/1962 Brunt 68--5 3,196,642 7/1965 Terhune et al. 685

IRVING BUNEVlCH, Pr'imary Examiner. 

1. A METHOD OF CONTROLLING THE STEAM IN A CLOSED TREATMENT CHAMBER FOR TEXTILE MATERIALS WHICH IS EXPOSED TO EXTERNAL ATMOSPHERIC PRESSURE, IN WHICH SAID MATERIAL PASS INTO AND OUT OF SAID CHAMBER THROUGH INLET AND OUTLETT OPENINGS EXPOSED TO SAID ATMOSPHERIC PRESSURE, SAID OPENINGS ALLOWING GASES TO PASS INTO AND OUT OF SAID CHAMBER UNDER SUFFICIENT DIFFERENTIAL PRESSURES, SAID METHOD COMPRISING ADMITTING STEAM UNDER PRESSURE INTO SAID CHAMBER SENSING THE PRESSURE OF SAID STEAM IN SAID CHAMBER, AND CONTROLLING THE ADMISSION OF SAID STEAM TO MAINTAIN SAID STEAM IN SAID CHAMBER AT A CONSTANT PRESSURE WHICH IS ABOVE ATMOSPHERIC PRESSURE TO PROVIDE TREATMENT OF SAID MATERIALS, BUT BELOW THE PRESSURE WHICH WOULD ALLOW THE ESCAPE OF SUBSTANTIAL AMOUNT OF STEAM THROUGH SAID INLET AND OUTLET OPENINGS. 